Hobby Lobby's Telemaster 40.....Electric Conversion Project
The Telemaster 40 kit was purchased from Hobby Lobby with full intenet to build it as my first large electric airplane. A great experiment that promises to be a learning experience.
I have several power choices and used rails on the fuse sides that will hold different motors easily. The 1/4 ply firewall that came in the kit is now 1/8th ply to save weight.
The large 850 sq in wing has a 73 inch span. I built it on my wing jig to insure straight construction.
I am using the flap function and am also using aileron servos mounted in the outer wing panels. I did not want to use the bell crank linkage shown on the plans.
Approximately 58 holes were "hole sawed" into the airframe to reduce weight. This included the landing gear block as well as the center of the aluminum gear. Every gram helps.
Things are looking better after 3 evenings at the building table. I'm still building and changing as I go...
Windshield / top hatch screw in place and the motor battery can be accessed without wing removal. The front of the fuse has laminated tips to strengthen without using the balsa filler blocks in the cowl area. Less weight!!
The battery box was built up around the battery pack size but is much longer than needed. Once glued in place the battery pack can be shimmed forward or rearward for airframe balance. Use a lot of holes to let heat out of the pack. 16 cells will be used on the first trial motor.
Air enters a large hole behind the motor and exits to sides of the fuse using the "plastic spoon" technique. This helps cool the warm pack. Servos are mounted rearward for easy installation as the battery box is lower there.
The battery box can bee seen with the windshield removed. Speed control and switchs are in the area where a fuel tank would be on a glow version. Lots of room in this large airframe to mount parts for easy balance.
This Astro 40 geared is powered by 16 each 2400ma cells and turns a 14-6 prop. My first motor choice was a pair of speed 600's on the 2-1 reduction box. It flew good with the twins but I intend to test a lot of combos...this is powerful!
Shown at the field after the first flight. What a great flying airplane!!! It is 2oz under my 8 pound projection and I am VERY happy with everything about this project.
It first flew 3 weeks and 3 days after dumping out the kit in the shop. It builds easy and fast, even considering the time spent head scratching with the electric conversion. It takes off the grass runway as easy as any 40 glow powered version. Flights are set at 8 minutes and then I look to land. My speed control has no BEC so the motor will never die without notice but I am wanting to make sure I can enjoy a nice landing after flying this great machine. The flaps are not needed with any head wind but are sure fun to play with. They cause the nose to pitch up so I have mixed down elevator using my Futaba computer radio. I have mixed a bit of rudder into the aileron control as well. These mixes make for an extrememly smooth flying airplane. I'm having a ball with this....if you are ever so inclined...give this a try. Let me know how you progress, or if I can help.... Enjoy!!!
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